I run ALL my bikes with right-front (always have and always will). I'm right-handed and like having the front on my best hand. Also, if I'm drinking or fiddling with something on the bike & need an emergency stop while my right hand is busy, the left-rear lever won't toss me over the handlebars.

I (and Sheldon Brown) may be in a minority on this, but we're doing it for good reasons.